腹部手术后病人出现呼吸困难、发绀、呼吸音减弱或消失，应首先考虑
A．切口感染B．肺不张和肺炎C．气胸D．血胸E．支气管炎
参考答案：B
Mrs. Brown was much disappointed to see the washing machine she had had ____ went wrong again.
A．it
B．it repaired
C．repaired
D．to be repaired
南极的平均气温为－25℃，最低气温－88．3℃，在那里考察队用的液体温度计是酒精温度计而不用水银温度计，这是因为（ ）
A．酒精比水银颜色更浅
B．酒精凝固点比水银凝固点更低
C．酒精沸点比水银沸点更低
D．酒精气体无毒，水银气体有毒
